Duck Curve Screensaver
The Duck Curve screensaver plots today's live grid demand for Great Britain hour by hour, showing the real solar-driven midday dip and evening ramp utilities call the "duck curve" — key-less, live from the National Grid Carbon Intensity API. It's free, runs in your browser, and ESC exits.
How the Duck Curve screensaver works
The saver fetches today's real half-hourly demand and generation-mix data for Great Britain's grid.
The curve plots demand across the day, dipping as solar output peaks at midday and ramping as the sun sets.
An optional overlay shows solar's real share of generation across the same hours.
The line grows through the day as new real readings publish.
A worked example
Around midday on a sunny day the curve dips as real solar generation peaks, then climbs sharply into the evening as solar fades and demand stays high — the actual duck-shaped curve grid operators watch for.
Settings & tips
- Solar overlay adds the generation-share line alongside demand.
- Accent recolours the demand curve.
- The curve fills in as the real day progresses — mornings show a shorter line.
Frequently asked questions
- Whose grid is this?
- Great Britain's — the National Grid Carbon Intensity API, a free, key-less, official real-time source.
- Why "duck curve"?
- The demand shape — high morning, a midday dip from solar, a steep evening ramp — resembles a duck's silhouette, a well-known term in grid planning.
- Is a key needed?
- No. The API is free and key-less.
- Is it free?
- Yes — free, no download, in your browser.